Rotary centrifugal mineral hydro-extractor of the horizontal type



Oct. 12 ,1926.

F. D. LEWIS ROTARY CENTRIFUZIAL'MINERAL HYDRO EXTRACTOR OF THE HORIZONTAL TYPE Fil ed mm 9, 1925 5 Sheets-Sheet l- IINVENTOR Oct. 12 1926. Y

F. D. LEWIS ROTARY CENTRIFUGAL MINERAL HYDRO EXTRACTOR OF THE HORIZONTAL TYPE INVENTOR I 12 b N JYJMZpgATTORNEY Oct. 1. 2 1926;

F. D. LEWIS ROTARY CENTRIFUSAL MINERAL HYDRO EXTRAGTCR OF THE HORIZONTAL TYPE 5 Sheets-Sheet 3 Filed Mav 9, 1925 w Y I Q INVENTOR 4% J? ATTORNgY.

7 1 I F. D. LEWIS ROTARY CENTRIFUGAL MINERAL HYDRO EXTRACTQ R OF IEE HORIZONTAL TYPE Filed Mav 9, 1925' 5 Sheets-Sht 4 INV EN TOR 45" ATTORNEY F. D. LEWIS ROTARY CENTRIFUIIAL MINERAL HYDRO sxTaAc-mofi jF- iius HORIZONTAL TYPE Filed 515v 9, 1925 5 Sheets-Sheet s ///////////////////////Ali-V//////%Hli ///////fil{ Patented fictrlz, 192$.

. FRANK n. LEWIS, or nnnvnnjooroneno.

Application filed May '9, 1925, Serial no. 29,151.

- My invention relates tofa rotary centrifthe cylin'ders which, owing to the centrii? ngal. action oftheir fastrotary movement, :act to extract the gold and'thennneral conuugal ,miiieral hydro extractor of the horizontal type.

' Theprimaryobjectofthe invention is to provide an apparatus Comprising a series of 7' spaced concentratingcyllnders which are v p I I proved centritugal mineral hydro extractor. V

open at one end and whichlie one within another and are connected to rotate in uni-- 'son,"saidcylinders' being 'inclosed in and e bolted to a cylindrical housing having 1101- low axial trunnions which ,are' mounted in bearings andwhich act respectively to supply screened placer ground or ore pulp. t0

Ieentrates therein, andto discharge the tail- 1 ing having heads provided with hollow truningstherefrom. I

Further, to provide a rotary centrifugal mineral concentrating and placer or other tree gold amalgamating apparatus comprise inga horizontally disposed cylindrical housn onsw'hich are supported in bearings, said housing inclosing aseries of spaced cylinders,

which are open at one end andWhich lie one withinanother, the'closed ends of the cylinders being bolted tothe'heads ofthe housing in alternate order,the inner facesof said cylinders being provided with annular. i g1'ooves,,the' innermost cylinder being 00a. I

respectively, of an impeller that, is'secured tinuously suppliedwith ore pulp through one of said hollow trunnions, said pulp'be-.-

ring forced byhentrifugalaction from cyl- Iindertocy'linder, said-cylinders being also j supplied with quicksilver which' fills the grooves therein, under centrifugal. action,

I oongestingjtheflow of tailingsto the tail-' the discharge end of the-housing, the tailiaigs being: discharged through the other hollow trunnion. I i Further, to provide an apparatus ofthls character, havingadjustable means for defining a concentrates discharge outlet andi'or regulating the flow of the concentrates .m'ough said outlet, adjustable means for of a portion of the same.

ings discharge and rotarym'eans for retard ing the ,tailings outflow. These, and other objects to be'hereinafter set forth, are accomplished bythe' mechanism illustrated in the accompanying 4 drawings, in which Figure 'l'is a side elevation of the im- Figure 2 is-a vertical -longitudinal ,sec-

"tional viewoit the same, 1 V V Figure 3 1s a vertical transverse sectional 'yiew on the line 3-v3 of Figure 2. s

Figure & isafia view of the disch" rge end of the machine, the impeller "being omitted for -Figure' 7 is an end View of the second concentrating cylinder; r Figure 815 a horizontal 360 0101131 View of- .a portion-of the same."

Figure 9 is an: end View of the third concentrating cylinderi Figure 10'is a portion of thesame. I v

Figure 11 isan end View of the fourth. or outermost concentrating cylinder.

FigurelQ- is a horizontal sectional View of a portion of the same.

1 Figures 13 and Hare. front and rear Views .pon the frontend of the first or innermost cylinder.

Figure 15 is a-itront end view of a half part H of the 1 concentrates discharge ring which lies over the discharge fend of the shell or llOLISlDg which enclosesthe concen:

t ating cylinders.

' F'gure'ldis a sectional view ofthe same;

Figure lZ- is' a sectional view'ofan ad-- ustable r ng which acts n conjunctlon wlth the concentrates discharge ring for controlling the discharge of theconcentrates.

horizontal section of Figure'18' is a front Viewof a half part of the ring shown'in Fig'urel'f.

Figure 19 is a' front View of an ring for congestin'g the outflow of material in the passage leading tothe tailingsjdischarge outlet.

Figure 20 is a sectional view o fthe samefj adjustable e ferj to simih r nion.

end of the outermost concentrating cylinder.

Figure 23 is asectional view showing one way of securing the ends of the two-part tubular concentrates-rcceiving ring.

Figure 2d is a similar view showing a diliierent way of securing the ends of said ring, and I Figure 25 is a detail sectional: view' on the line 25-25 of Figure 4E.

Similar reference letters and numbers reparts throughout the drawings. 1 Y

' Referrirw to the accompanying drawings: The numeral 1 designates the bed plate 0' the apparatus, which is provided with narrow depending side and end portions which terminate in a "flange 2, which rests upon the foundation or floor the flange being provided with aperture-d lugs 3 for the reception of bolts or lag screws by which the bed plate is secured the floor Upon the opposite end portions of the bed plate are formed raised portions or bosses l to which are bolted standarcs 5 and 6 having roller bearings 7, in which are mounted hollow shaits or trunnions 8 and 9 respectively, which are rigidly mounted in the hubs 1'0 and 11; which are formed on caps or heads 12 and 13 respectively. which are bolted upon the ends'o't' a cylindrical casing 14: which will hereinafter be more particularly referred to. The hollow trunnion 8 extends beyond the standard 5 and has rigidly mounted thereon a driven pulley 15, which is adapted to be belted to a driving pulley, and an" idle pulley 16 is loosely mounted thereon. adjoining the pulley 15. A collar 17 surrounds the trunnion 8 between the hub of the idle pulley and the standard 5, and a collar 18 is secured on the outer end portion of the said trunnion by a set screw 19, and these collars prevent endwise movement of the pulleys on the trun- The outer portion of the trunnion 8 is counterbored for a suitable distance, and

-this counterbore is again .counterbored to ceive a pipe-not shown-tlrough which ore pulp (which is finely ground ore and water) is supplied to the apparatus.

The inner face of the cap or head .12 isformed with a circular boss 24. which is concaved as shown at 25 in Figure 2, the

surface of the concavity being curved in Tlie first and third 01 these cylinders are bolted to the head 12 'olthe casing in the iellowinp; manner: The head 26- 'of the first cylinder A is inset from the adjacent end of the cylinder and this end of the cylinder fits over the boss 24 andis formed with a flange 27 which is provided with a circular series of threaded holes-28, as clearly shown. in Figures '5 and 6; This cylinder extends to within a short distance of the opposite casing head 13, and terminates in an annular introverted lip 29, the purpose of which. will hereinafterappear. The flange 27 of this cylinder is spaced from. the casing head 12. andhetween the flange 27 and the said. head 12. fits an introverted flange 30* which is formed on the front end ct the third cylinder C; which is concentric with the first cylinder and spaced therefrom.

The third cylinder C, is of the same length as the first cylinder and also terminates in an annular introverted lip 31-. The flange 30 of the cylinder G is provided with a series of threaded holes 32', (see Figures 9'and' 10) and cap bolts 33 are passed through holes in the head 12 and throughthe threaded holes in the flanges 27 and 30 of the cylinders A and C" respectively as clearly shown in Figure 2, thereby securing these cylinders to the head 12. I i

The head 26 of the cylinder A is with a boss. 34 over which fits the open end of'a spacing cylinder 34, which lies withinthe concentrating cylinder A, and extends slightly beyond the open end of the same and terminates in a closed end 35. Against this end 35', is placed the closed end 36, of the second concentrating cylinder B, which extends in between the cylinders "A and C, and terminates in an annular introverted lip37, which is spaced from the flange 27 of the cylinder A.. The end 36 of the cyliner B is flanged as shown at 38 in Fig ures 2. and 8 and the flange is provided with a circular series of threaded bolt holes 39.

Against the end 86 of the cylinder B is placed the end 40 of the fourth concentrating' cylinder 1), which surrounds the third cylinder C and terminates near the casing head 12 in an annularintroverted lip 41. The head ends of the cylinders B and D are provided with registering holes 42 and formed whichmay be increased or diminished, as

may be found necesssary by turning the formed with an annular recess 66 (see Figure 2) in which are seated two rings 67 and 68, the ring 68 fitting snugly within the ring 67, and the two rings fitting snugly in therccess 66. The inner face of the ring 67 is beveled at its circumferential edge portion, as shown at G, in Figure 17, and this beveled edge lies directly behind the marginal edge of the opening in the ring (2, and is adjustable with respect to the said marginal edge, to define an outlet from the casing for the concen ,rates, as will be hereinafter more particularly referred to, and this ring is adjusted to vary the outlet space, in the following manner Four bolts 69 are screwed head 13 andezztend slightl through the beyond the bottom of the annular recess 66 in the said or increases or diminishes the space between it and the ring 62, which space is the outlet space for the concentrates.

As shown in Figure 2, the rings 67 and ,68 are behind the head end of the cylinder D, but are spaced therefrom, and this space.

forms the entrance to an axial out et recess or chamber '73, in the casing head'13, which is of conical form, and the retarder 1 1, which is bolted to the end of the cylinder 1), lies in this outlet, and is provided with blades 4: 1, which stand at right angles to the circular body of the retarder, are

7 highest at their inner ends, and slope down toward their outer ends, where they merge into the face of the body 4 1, as shown in Figure 2. The ring 68, is also an ad ust able ring and is positioned at the entrance to the outlet chamber 73, in the head'13, and its function is to congest the outflowing material at this point, so that the concentrates may be permitted to pass out between the rings 62 and 67, and are thus prevented from being carried into the outlet chamber -7 3, with the tailings.

The ring 68, is slidably mounted on the eight bolts 45, which connect the cylinders 13 and D with the head 13, and it is adjusted by four bolts 74, which are screwed through the head 13 and are connected to the ring 68 by screws 75, which pass through the ring and into threaded holes in the bolts 74,

in the same manner thatthe ring 67, is secured to the bolts (39. Thus, the ring 68 may be moved inward to contract the space leading to the outlet chamber 7 3, thereby causing a congestion of the outflowing material by which the concentrates which constitute the heaviest particles ofthe material may be carried, by centrifugal action, through their proper outlet, while the lighter particles or tailings pass over the concentrates and into the outlet chamber 73. A flat ring 76, is secured upon the circumferential edge of the rear flange 61, of the casing 14, and projects inward beyond the flange. A similar flat ring 77 is also secured upon the circumferential edge of the casing head 13 and extends inward over the ring 7 6, but is separated from it by a slight space.

The inneredge portions of these two rings project through an annular slot 78,- in a stationary tubular ring 79, whichsurrounds the casing let, adjacentits flange 61, and is heid between two angle plates 80, by bolts 81, whi -h pass through the plates and through the tubular ring, the horizontal flanges of the angle plate 80 being bolted to the bee plate 1, this arrangement being clearly shown in Figures2, 3 and 4:. I

The tubular ring is preferably divided into two semi-circular parts and the ends of the two parts may be connected as shown in Figure by short sections of tubing 82, which are inserted in the meeting ends of the ring sections so as to lie partly in each ring section, and which are secured by screws or rivets 83 to the said section; or the meeting'ends of the ring sections may be flanged as shown in Figure 2 1, and the flanges connected by bolts 85. The tubular ring 79 constitutes a concentrates receiving and discharging ring, and a part of the? ring, at its lowest point, is cut off on a horizontal line, as shown at 86, in Fi ures 2 and 3, to provide an outlet opening from the ring.

A trough 87 having an inclined bottom. is placed between; the angle plates 80 and directly beneath the opening in. the ring, and this trough receives the concentrates from the ring and conveys them to a suitable receptacle-not shown;

The outlet chamber 73 in the head 13, tapers to a' diameter corresponding to the bore of the hollow trunnion 9 which receives the coarse product or tailings from the said chamber and discharges it through'its outer end. The outer end of the trunnion 9 is threaded and the hub of a runner is'screwed thereon. This runner comprises a pair of spaced parallel disks 88 which are united by four equidistant radial blades 89 which extend from near the center of the disks lit) to their circumferential edges. The advance 4 sides of these blades are curved as shown hub of the runner has an-axial hole 91, which forms communication between the hollow trunnion 9 and the space between the; runner disks, the material passing through said trunnion being drawn into the spacebetween the runnerdisks and out through the passes 90be'tween the blades 89. The runner is enclosed in housing 92, which is thesame character of housing as that of the common type of centrifugal pump, and comprises duplicate members which are each forined with circularichambers, and with flanges 93' which are connected by bolts 9% to form a housing which is of the outline shown in cross'section in Figure 2, and in the dotted side view in" Figure 4. p a r M A short horizontally disposed lateral outlet pipe or nozzle 95, is formed at thelowest point of the housing, and is preferably threaded at its end portion to connect with; a pipenotshownwhich conveys the tail- D, are first'supplied with quicksilver, and

this is done by removing the bolt 57 and in serting the spout of a funnel through the opening 56, in the casing lc, and through the alined openings in the several cyllnders until the innermost cylinder A 71s reached,

the end portion of the funnel spout being outwardly curved, so thatwhen the spout is inserted in the hole of one cylinder its outlet end will be beyond or on one side of the hole in the next cylinder,-and thus prevent any of the mercury supply for one cylinder from being poured into the next cylinder. The amount of quicksilver for each cylinder is previouslydetermined, and

the introverted annular lips on the open ends of the cylinder are deep enough to confine the quicksilver in each cylinder until the v apparatus is put in motion, and whentheap' paratus is running under the required number of revolutions per minute, which is from two hundred and fifty to five hundred revolutions, the quicksilver, under centrifugal force, will fill the annular grooves in each cylinder, as well as the longitudinal grooves,

flush with the surface of the cylinder, andeaoh ring of quicksllver will then constitute an amalgamating surface; rThe machine 13.

started and placer ground, screened to small gravel and, the sandsof thebeds of rivers mills, which is finely ground oremixed with water, in the proportion of about nine parts or" water and one part of ore, is then supplied through the tube 22 and hollow trunnion 8, to the chamber 25 in the head 12, where it is carriedxby the blades ofthe impeller '52, and under centrifugal action, to

the rim of the said chamber which is curved as shown and directsthe pulp against the end of the innermost cylinder A. The pulp passes through the slots 54:, in the end of this cylinder, and into the cyluinder Where.

under centrifugal action, it is forced against the wall of the said cylinder. The gold which is the heaviest substance in'the ore, will hug the surface or the cylinder, and as the material is pushed forward by the con tinuous incoming supply,-the gold will come in contact with the quicksilver in the cylin- 7 der'grooves, and will be caught thereby, and

the'other elements in the pulp will automatically arrange themselves in the order of- 7 their specific gravities. Thus the ore is given both a concentrating and an amalgamating treatment as it passes over the surface ofthe cylinder. The concentrated product less that part of the gold caught by the quicksilver, passes through the open end of cylinder A into cylinder B and undergoes the same action as in A, and from cylinder 13 it passes intocylinder' 5C, and thence into cylinder D, whence it passes into the casing 14, where it. receives a concentrating but not van amalgamating treatment. From the casing, the concentrates pass through the outletspace betweenfthe rings 62and 67, the ring 68 being adjusted to conge'stthe outflow from the cylinders, so that the concentrates may pass through their proper openlng and not be carried out with the coarse product. From the opening between the rings 62 and'67, the concentrates pass into thespacebetween the ring-'62 and the casing head 13, and as the face of the ring 62 inclines with re spect to the face of the head 13'see Figure I 2the' space between them widens toward the fiat rings and vthus preventing clogging I of the concentrates in the said space, and from this space the concentrates pass between the fiat rings '76 and 77 to the tubular ring 7 9, and thence into the trough 87, which conveys them to a suitable receptacle r01; -i urther treatment.

The coarser product, ortailings, passes into the chamber 73 in the 'headf13, but the blades 44 on the retarder disk 44 in" said chamber, retard the outflow ofthe-tail ings, thus enabling any heavy material thereinto be thrown outward by centrifugal force and be carried out with the concentrates. The tailings pass into the hollowtrunnion 9, and'the blades 89 of the runner disks 88, create a suction through the said and creeks, or the pulp from ore treating trunnion by which the tailings are rapidly and continuously drawn through the said trunnion and runner to the housing 92 and out through the discharge pipe of said housing. All adjustments can be easily and quickly made and the roller bearings 7 enable the machine to be operated with only the minimum'ot friction, the bearings being lubricated by means of oil cups 97 which are screwed into the tops of the standards 5 and 6.

After any desired quantity of ore has been run through the apparatus, the cylinders may be flushed by running pure water through them while the apparatus is rotat ing; then it 'is brought to a standstill and bolt 58 is removed, and the mercury in each cylinder will run from the annular groove 55 into the longitudinal channels 59 and throughthe holes 58 in said cylinders, and out through the hole 56 in the casing and into a receptacle. The gold is then separated from the niercuryvin the usual manner, as by forcing the mercury through chamois skin, and the mercury is reserved for further use.

Having described my invention, what I claim as new, and desire to secure by Letters Patent is:

1. In an apparatus of the character described, a cylindrical casing, a series of spaced cylinders in said casing which are arranged one within another and connected to said casing, said cylinders being open at one end, the open end of one cylinder being next to the closed end of the surrounding cylinder, means defining an inlet to the innermost cylinder, adjustable means for defining an annular outlet space from said casing, means for defining an axially alined outlet from said casing, and means for rotating said casing.

52. In an apparatus of the character described, a rotatable cylindrical casing having an axial inlet at one end and an axial tailings outlet at its opposite end and adjustable means for defining an annular concentrates outlet space in said opposite end; a series of spaced cylinders in said casing which are open at one end and arranged one within another and connected to said casing, the open end 01 one cylinder being next to the closed end of the surrounding cylinder, a-

tubular ring surrounding said caslng and having an annular slot and an outlet opening and means'defining an annular passage connectingsaid annular outlet space and said slot.

a 3. in an apparatus of the character described, a cylindrical casing having heads provided with hollow trunnions and bearings for SELlCltl'LlIlIllOliS, said trunnions clefining an inlet and an outlet to said casing, an'adjustable ring in theoutlet end of said casing for defining an annular outlet, a tubular ring surrounding-said casing adjacent to its outlet endand having an annular slot and an outlet opening, means defining an annular passage connecting said annular outlet and said annular slot, a series of spaced cylinders in said casing which are open at casing, the open end of one cylinder being spaced from the closed end of the surrounding cylinder, the casing inlet communicating with the innermost cylinder.

4. In apparatus of the character de scribed, a cylindrical casing having heads provided with hollow trunnions which provide an inlet and an outlet for said casing, and supporting bearings for said trunnions, a space being provided between the discharge end of the casing and the adjacent head, adjustable means for defining said since, an adjustable ring in said latter head which acts in conjunction with the end of the casing to define an annular outlet to said space, a stationary tubular ring surrounding said casins' adjacent to its discharge end having an annular slot and an outlet opening and means defining an annular passage connecting said space and the annular slot in said ring; a series of spaced cylinders in said casing which are open at one end and arranged one withinanother, their closed ends being connected in alternate order with the respective casing heads, each of said cylinders being providec internally with a series of annular grooves, and the innermost cylinder being connected with the casing inlet.

5. In an apparatus of the character deprovided with hollow trunnions which define an inlet and an outlet for said casing, and bearings for said trunnions,-the head at the outlet end of the casing being spaced from said outlet end, and adjustable means for defining said space, a series of spaced cylinders in said casing which are closed one end and arranged one within the other and connected in alternate order with the casing heads, a space being provided between the clos'ed end of the ouermost cylinder and the outlet head of the casing which communicates with the outlet through the adjacent trunnion, adjustable means in the read for contracting said space, an adjustable ring in said head which acts in con junction with the end of the casing for de- V fining an annular opening into the space between the end ofthe casing and the head,

end otthe casing and its head, said rings jro ectin into the slot in said tubular rin a a i I Q scribed, a cylindrical casing having heads nionsr and a series of spaced cylinders in said casing which are closed at one end and arranged one within another, their closed ends belng secured 1n alternate order to .the casing heads, the innermost cylinder being connected with the'inlet passage, saidcylinders belng pro'vlded with annular internal:

grooves, said innermost j cylinder being adapted to receive a continuous supply of ore pulp which is passed through the succeeding cylinders under centrifugal action,

whereby the heavier particles or concen-- crates are separated from the tailings, means defining an annular outlet at the rear saidcasing for the concentrates and an adjustable ring for contracting or enlarging said outlet, a passage being formed between the outermost cylinder head and the ad jacent casing head which opens to the outlet trunnion and adaptedto receive the tailings,

adjustable means for congesting the material entering said passage, a retarding ele ment in said passage, sald cylinders belng adapted to receive quicksilver which fills inders having diametrically opposite alined a threaded holes constituting inlets and out-1' lets for. quicksilver, and bolts which noi mally close sald holes, means defining an axial inlet connecting with the innermost cylinder whereby ore J pulp is continuously supplied to said cylinder and passes through thesucceeding cylinders under centrifugal action, said cylinders beingsupplied' with quicksilver which fills said, channels whereby'the ore is subjected-to both a concentra ting and "an amalgamating act-ion, an

annular concentrate outlet in the rear end ofsaid casing and adjustable m'eansj'for'en larging or contractlng'said outlet, means delining an axial outlet -"passag'e from said casing for the taillngs, means for retarding with the interior'of the the outflow to said outlet and an impeller at the end of said outlet. j 7

-' 8. In a horizontallydisposed centrifugal v concentrating and amalgamating apparatus,

the combination with a rotatable casing having a flanged rear end of a head secured to said end but separated therefrom by a spaceand means for defining said space, an adjustable ring in said head which acts in conjunction with the end of said casing to define an outlet to said space, a tubular stationary ring surrounding said casing adjacent its rearend and provided with an annular slot, a fiat ring secured to the easing flange and projecting into said annular slot, a'flat ring secured to the cylinder head and surrounding the first flat ring but spaced therefrom and also extending into said slot, said rings defining an: annular passage connecting the space between the casing flange and head with the interior of the tubular ring, an axial outlet being formed in said head. 9. In a horizontally disposedcentrifugal concentrating and amalgamating apparatus, the combination with a rotatable casing, of a rear head secured thereto, but spaced therefrom, and having an axial outlet, a ring on the end of said casing having a slightly smaller opening than the bore Of a said casing, 21 ring adjustably mounted in 1 an annular recess in said head which acts' in conjunction with-the first ring to define an annular concentrates opening communieating with the space between the casing and its head, means for increasing or diminishing the space between the end of the c asing and its head, areceiver and means defining-a passage between said receiver and said vspace. I v 10. In-a horlzontally-disposedcentrifugal concentrating and amalgamating apparatus,

the combination with a rotatable casing,,a sense of spaced concentric ore concentrat:

ing cylinders therein, which are closed at head and means for contracting or enlarging said outlet, a space being provided between the closed end of the: outermost cylinder andv said head, an adjustable ring in I said head :for contracting said space, a tardingelemention the end of said cylinder which enters the annular chamber in the said head, an impeller'at the end of said outlet passage, a receiver and means defin- ;ing a passage connecting said receiver wit-1r the space between the casing and its head.

11. In a horizontally disposed centrifugal concentrating and amalgamating apparatus, a rotatable cylindrical casing having heads provided with hollow trunnions which form respectively an inlet to and an outlet from said casing and bearings for said trunnions,

spaced concentric cylinders in said casing which are closed at one end, the closed ends being connected to the casing heaos in alternate order, said cylinders having annular internal channels, and introverted lips at their open ends, a spacing tube between the closed ends of the innermost cylinder and the second cylinder and an axial bolt extending through the closed ends of said cylinders, said innermost cylinder having a circular series of inlet openings in its closed end, an impeller secured to said closed end by said axial bolt having blades leading to said openings whereby ore pulp passing through the inlet trunnion is carried into the first cylinder and through the succeeding cylinders under centrifugal action, an arnular outlet in the rear end of the casing for the concentrates, and means for contracting or enlarging said outlet, a passage leading to the outlet trunnion, and means for contracting said passage.

12. In a horizontally disposed centrifugal concentrating and amalgamatin ai iparatus, the combination with a cylindrical casing having a flanged rear end, a head secured to said flanged end but separated thereirom, by

1 let opening.

space bolts in said head which abut against the end of the casing to define said space and means defining an annular outlet from the casing to said space, of a stationary tubular ring which surrounds said casing adjacent said flange, and provided in one side with an annular slot, a fiat ring secured to said ti;

surrounding the first fiat ring but spaced thercfron'i, said flat ring extending into the annular slot in said tubular ring and defining a passage connecting said tubular ring and the space between the casing and its head, whereby material discharging from the cas- Iito said space is conveyed to said tubring, said tubular ring having an out- 13. In a horizontally disposed centrifugal concentrating and amalgamating apparatus, the combination with a rotatable cylindrical casing having heads provided with hollow trunnions constituting an axial inlet and an azcial outlet and concentric concentrating and go, a flat ring secured to said head and the end of the casing to define an annular outlet for the concentrates and an adjustable i ring in the rear casing for contracting the entrance to the axial outlet.

14:. In a horizontally disposed centrifugal concentrating and amalgamating apparatus,

a rotatable casing having hollow axial trunnions constituting an inlet and an outlet, spaced concentric cylinders in said casing and movable therewith, the innermost cylin der communicating with the inlet trunnion and the outermost cylinder opening into said casing, a space being defined between the head of the outermost cylinder and the adjacent casing head which communicates with the axial outlet; an adjustable ring in the rear casing head which acts in conjunction with the adjacent rim of said casing to dehne an annular concentrates outlet from said casing and an ad ustable ring witlnn the first ring which acts in conjunction with the head of the outermost cylinder to contract the space communicating with the outlet trunnlon. I

15. In a horizontally disposed centrifugal czmcentrating and amalgamating apparatus, cylinder op E at one end, said open end terminating in introverted lip, said cylind er having a series of internal annular channets and a longitudinal channel which intersects said annular channels, and diametrically opposite threaded holes, one of which is at the intersection of the longitudinal channel and one of the annular channels,

16. In a mineral hydro extractor, the com bination of a base plate, standards provided with bearings; horizontal hollow shafts rotatablymountedin said bearings; a group of spaced concentrically arranged cyllnders secured to each other and to sald shafts, each of said cylinders except the outer one being provided on its inner face with spaced an- 17.- In a mineral hydro extractor, the combination with a base plate and bearing standards mounted thereon, hollow shafts rotatably mounted in said bearings and arranged to support a mineral hydro extractor .between them, one of which hollow shafts forms the mineral pulp inlet to said extraotor and the other the tailings discharge outlet from said extractor, said mineral hydro extractor comprising two oppositely positioned heads facing each other and'secured to the inner ends of said hollow'shafts and a cylindrical casing secured between said heads, a plurality of spaced amalgamating cylindrical casings Within said outer cylindrical casing, means for rotating said Shafts and said mineral hydro extractor, and means for feeding mineral pulp into said hollow shaft and into and through said hollow discharge shaft, and means including a fixed tube surrounding said rotating outer casing,

'a concentrates passageway being provided 1 for receiving the concentrates from said amalgamating cylinders and said outer casing and discharging it into said fixed tube.

In testimony whereof I aflix my signature.

FRANK D. LEWIS. 

